This invention relates to conveying apparatus of the powered roller type in which the rollers are individually driven.
The use of slip drive devices in roller conveyor apparatus are well known in the industry. Examples are found in U.S. Pat. Nos. 2,976,981 and 4,006,815. For example, the former discloses a sprocket driven roller in which the sprocket drives the roller by virtue of the frictional forces between the hub of the sprocket and the roller. As the line pressure of the loads increase on the surface of the rollers and provide a counter-torque force, the sprocket being constantly driven begins to slide within the sleeve and accumulation occurs.
The advantages of a slip drive become very important in environments requiring or exposing the surfaces of the rollers to objects which may become lodged between rollers. Damage to the object or rollers could result when roller is positively driven by the driving means. Having the slip function designed into the apparatus minimizes the damage since the counter-torque imposed by the jamming articles overcomes the torque due to the frictional force and the roller becomes stationary.
The present invention provides additional advantages to a slip frictional drive as will be understood by reading the ensuing description. The simplicity of the invention will also be evident.